Brussels : European Commission President Jean-Claude Juncker, left, pats British Prime Minister Theresa May on her back upon her arrival at EU headquarters in Brussels, Wednesday, Nov. 21, 2018. AP/PTI Photo)

The European Union and Britain agreed Thursday a draft declaration on their post-Brexit relations that sets out an “ambitious, broad, deep and flexible partnership,” officials said.

The two sides have also agreed a draft deal extending the transition period by one or two years beyond the end of 2020, a final sticking point of the divorce deal.

European Council President Donald Tusk said the EU executive, the European Commission, informed him it has agreed the political declaration on the future ties with Britain.

“I have just sent to EU27 a draft Political Declaration on the Future Relationship between EU and UK,” said Tusk, who represents the 27 remaining EU member countries.

“The Commission President (Jean-Claude Juncker) has informed me that it has been agreed at negotiators’ level and agreed in principle at political level,” Tusk tweeted.

He said EU leaders still have to endorse the draft declaration, which is due to accompany a draft of agreed terms for Britain’s withdrawal from the bloc on March 29.

The EU leaders are due to meet at a summit in Brussels on Sunday to endorse both documents.

“The declaration establishes the parameters of an ambitious, broad, deep and flexible partnership across trade and economic cooperation” and other areas, according to a copy of the document seen by AFP.

The other areas cover law enforcement, criminal justice, foreign policy, security and defence and wider areas of cooperation, according to the draft.

In an update of the withdrawal agreement, both sides have agreed to extend the post-Brexit transition period from December 31, 2020 “for up to one or two years.”

The transition period is designed to allow governments and businesses to adjust to a new relationship after more than four decades of close ties.

Following the announcement of the draft declaration, the British parliament said Prime Minister Theresa May will make an “emergency statement” to MPs on Thursday.

Downing Street said the prime minister was holding a teleconference with cabinet ministers about the deal.